From 4a7f3067529c133ae280fa982372ec6c84f90c0a Mon Sep 17 00:00:00 2001
From: Niki Roo <niki@nikiroo.be>
Date: Mon, 21 Dec 2020 22:23:49 +0100
Subject: [PATCH] New: ui.Item

---
 src/be/nikiroo/utils/ui/Item.java | 479 ++++++++++++++++++++++++++++++
 1 file changed, 479 insertions(+)
 create mode 100644 src/be/nikiroo/utils/ui/Item.java

diff --git a/src/be/nikiroo/utils/ui/Item.java b/src/be/nikiroo/utils/ui/Item.java
new file mode 100644
index 0000000..c8afc7f
--- /dev/null
+++ b/src/be/nikiroo/utils/ui/Item.java
@@ -0,0 +1,479 @@
+package be.nikiroo.utils.ui;
+
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Dimension;
+import java.awt.Graphics;
+import java.awt.Graphics2D;
+import java.awt.Image;
+import java.awt.Rectangle;
+import java.awt.image.BufferedImage;
+import java.util.HashMap;
+import java.util.Map;
+
+import javax.swing.BorderFactory;
+import javax.swing.JComponent;
+import javax.swing.JLabel;
+import javax.swing.JPanel;
+import javax.swing.SwingConstants;
+
+/**
+ * A graphical item that can be presented in a list and supports user
+ * interaction.
+ * <p>
+ * Can be selected, hovered...
+ * 
+ * @author niki
+ */
+abstract public class Item extends JPanel {
+	static private final long serialVersionUID = 1L;
+
+	static private Map<Dimension, BufferedImage> empty = new HashMap<Dimension, BufferedImage>();
+	static private Map<Dimension, BufferedImage> error = new HashMap<Dimension, BufferedImage>();
+	static private Map<Color, JComponent> statuses = new HashMap<Color, JComponent>();
+
+	private String id;
+	private boolean selected;
+	private boolean hovered;
+
+	private String mainTemplate;
+	private String secondaryTemplate;
+
+	private boolean hasImage;
+	private JLabel title;
+	private JLabel secondary;
+	private JLabel statusIndicatorOn;
+	private JLabel statusIndicatorOff;
+	private JLabel statusIndicatorUnknown;
+	private Image image;
+	private boolean imageError;
+
+	private String cachedMain;
+	private String cachedOptSecondary;
+	private Integer cachedStatus;
+
+	/**
+	 * Create a new {@link Item}
+	 * 
+	 * @param id
+	 *            an ID that represents this {@link Item} (can be NULL)
+	 * @param hasImage
+	 *            this {@link Item} will contain an image
+	 */
+	public Item(String id, boolean hasImage) {
+		this.id = id;
+		this.hasImage = hasImage;
+		init(hasImage);
+	}
+
+	// Configuration :
+
+	protected int getMaxDisplaySize() {
+		return 40;
+	}
+
+	protected int getCoverWidth() {
+		return 100;
+	}
+
+	protected int getCoverHeight() {
+		return 150;
+	}
+
+	protected int getTextWidth() {
+		return getCoverWidth() + 40;
+	}
+
+	protected int getTextHeight() {
+		return 50;
+	}
+
+	protected int getCoverVOffset() {
+		return 20;
+	}
+
+	protected int getCoverHOffset() {
+		return 0;
+	}
+
+	protected int getHGap() {
+		return 10;
+	}
+
+	/** Colour used for the secondary item (author/word count). */
+	protected Color getSecondaryColor() {
+		return new Color(128, 128, 128);
+	}
+
+	/**
+	 * Return a display-ready version of the main information to show.
+	 * <p>
+	 * Note that you can make use of {@link Item#limit(String)}.
+	 * 
+	 * @return the main info in a ready-to-display version, cannot be NULL
+	 */
+	abstract protected String getMainInfoDisplay();
+
+	/**
+	 * Return a display-ready version of the secondary information to show.
+	 * <p>
+	 * Note that you can make use of {@link Item#limit(String)}.
+	 * 
+	 * @return the main info in a ready-to-display version, cannot be NULL
+	 */
+	abstract protected String getSecondaryInfoDisplay();
+
+	/**
+	 * The current status for the status indicator.
+	 * <p>
+	 * Note that NULL and negative values will create "hollow" indicators, while
+	 * other values will create "filled" indicators.
+	 * 
+	 * @return the status which can be NULL, presumably for "Unknown"
+	 */
+	abstract protected Integer getStatus();
+
+	/**
+	 * Get the background colour to use according to the given state.
+	 * <p>
+	 * Since it is an overlay, an opaque colour will of course mask everything.
+	 * 
+	 * @param enabled
+	 *            the item is enabled
+	 * @param selected
+	 *            the item is selected
+	 * @param hovered
+	 *            the mouse cursor currently hovers over the item
+	 * 
+	 * @return the correct background colour to use
+	 */
+	abstract protected Color getOverlayColor(boolean enabled, boolean selected,
+			boolean hovered);
+
+	/**
+	 * Get the colour to use for the status indicator.
+	 * <p>
+	 * Return NULL if you don't want a status indicator for this state.
+	 * 
+	 * @param status
+	 *            the current status as returned by {@link Item#getStatus()}
+	 * 
+	 * @return the base colour to use, or NULL for no status indicator
+	 */
+	abstract protected Color getStatusIndicatorColor(Integer status);
+
+	/**
+	 * Initialise this {@link Item}.
+	 */
+	private void init(boolean hasImage) {
+		if (!hasImage) {
+			title = new JLabel();
+			mainTemplate = "${MAIN}";
+			secondary = new JLabel();
+			secondaryTemplate = "${SECONDARY}";
+			secondary.setForeground(getSecondaryColor());
+
+			JPanel idTitle = null;
+			if (id != null && !id.isEmpty()) {
+				JLabel idLabel = new JLabel(id);
+				idLabel.setPreferredSize(new JLabel(" 999 ").getPreferredSize());
+				idLabel.setForeground(Color.gray);
+				idLabel.setHorizontalAlignment(SwingConstants.CENTER);
+
+				idTitle = new JPanel(new BorderLayout());
+				idTitle.setOpaque(false);
+				idTitle.add(idLabel, BorderLayout.WEST);
+				idTitle.add(title, BorderLayout.CENTER);
+			}
+
+			setLayout(new BorderLayout());
+			if (idTitle != null)
+				add(idTitle, BorderLayout.CENTER);
+			add(secondary, BorderLayout.EAST);
+		} else {
+			image = null;
+			title = new JLabel();
+			secondary = new JLabel();
+			secondaryTemplate = "";
+
+			String color = String.format("#%X%X%X", getSecondaryColor()
+					.getRed(), getSecondaryColor().getGreen(),
+					getSecondaryColor().getBlue());
+			mainTemplate = String
+					.format("<html>"
+							+ "<body style='width: %d px; height: %d px; text-align: center;'>"
+							+ "${MAIN}" + "<br>" + "<span style='color: %s;'>"
+							+ "${SECONDARY}" + "</span>" + "</body>"
+							+ "</html>", getTextWidth(), getTextHeight(), color);
+
+			int ww = Math.max(getCoverWidth(), getTextWidth());
+			int hh = getCoverHeight() + getCoverVOffset() + getHGap()
+					+ getTextHeight();
+
+			JPanel placeholder = new JPanel();
+			placeholder
+					.setPreferredSize(new Dimension(ww, hh - getTextHeight()));
+			placeholder.setOpaque(false);
+
+			JPanel titlePanel = new JPanel(new BorderLayout());
+			titlePanel.setOpaque(false);
+			titlePanel.add(title, BorderLayout.NORTH);
+
+			titlePanel.setBorder(BorderFactory.createEmptyBorder());
+
+			setLayout(new BorderLayout());
+			add(placeholder, BorderLayout.NORTH);
+			add(titlePanel, BorderLayout.CENTER);
+		}
+
+		// Cached values are NULL, so it will be updated
+		updateData();
+	}
+
+	/**
+	 * The book current selection state.
+	 * 
+	 * @return the selection state
+	 */
+	public boolean isSelected() {
+		return selected;
+	}
+
+	/**
+	 * The book current selection state,
+	 * 
+	 * @param selected
+	 *            TRUE if it is selected
+	 */
+	public void setSelected(boolean selected) {
+		if (this.selected != selected) {
+			this.selected = selected;
+			repaint();
+		}
+	}
+
+	/**
+	 * The item mouse-hover state.
+	 * 
+	 * @return TRUE if it is mouse-hovered
+	 */
+	public boolean isHovered() {
+		return this.hovered;
+	}
+
+	/**
+	 * The item mouse-hover state.
+	 * 
+	 * @param hovered
+	 *            TRUE if it is mouse-hovered
+	 */
+	public void setHovered(boolean hovered) {
+		if (this.hovered != hovered) {
+			this.hovered = hovered;
+			repaint();
+		}
+	}
+
+	/**
+	 * Update the title, paint the item.
+	 */
+	@Override
+	public void paint(Graphics g) {
+		Rectangle clip = g.getClipBounds();
+		if (clip == null || clip.getWidth() <= 0 || clip.getHeight() <= 0) {
+			return;
+		}
+
+		updateData();
+
+		super.paint(g);
+		if (hasImage) {
+			Image img = image == null ? getBlank(false) : image;
+			if (isImageError())
+				img = getBlank(true);
+
+			int xOff = getCoverHOffset() + (getWidth() - getCoverWidth()) / 2;
+			g.drawImage(img, xOff, getCoverVOffset(), null);
+
+			Integer status = getStatus();
+			boolean filled = status != null && status > 0;
+			Color indicatorColor = getStatusIndicatorColor(status);
+			if (indicatorColor != null) {
+				UIUtils.drawEllipse3D(g, indicatorColor, getCoverWidth() + xOff
+						+ 10, 10, 20, 20, filled);
+			}
+		}
+
+		Color bg = getOverlayColor(isEnabled(), isSelected(), isHovered());
+		g.setColor(bg);
+		g.fillRect(clip.x, clip.y, clip.width, clip.height);
+	}
+
+	/**
+	 * The image to display on image {@link Item} (NULL for non-image
+	 * {@link Item}s).
+	 * 
+	 * @return the image or NULL for the empty image or for non image
+	 *         {@link Item}s
+	 */
+	public Image getImage() {
+		return hasImage ? image : null;
+	}
+
+	/**
+	 * Change the image to display (does not work for non-image {@link Item}s).
+	 * <p>
+	 * NULL is allowed, an empty image will then be shown.
+	 * 
+	 * @param image
+	 *            the new {@link Image} or NULL
+	 * 
+	 */
+	public void setImage(Image image) {
+		this.image = hasImage ? image : null;
+	}
+
+	/**
+	 * Use the ERROR image instead of the real one or the empty one.
+	 * 
+	 * @return TRUE if we force use the error image
+	 */
+	public boolean isImageError() {
+		return imageError;
+	}
+
+	/**
+	 * Use the ERROR image instead of the real one or the empty one.
+	 * 
+	 * @param imageError
+	 *            TRUE to force use the error image
+	 */
+	public void setImageError(boolean imageError) {
+		this.imageError = imageError;
+	}
+
+	/**
+	 * Make the given {@link String} display-ready (i.e., shorten it if it is
+	 * too long).
+	 * 
+	 * @param value
+	 *            the full value
+	 * 
+	 * @return the display-ready value
+	 */
+	protected String limit(String value) {
+		if (value == null)
+			value = "";
+
+		if (value.length() > getMaxDisplaySize()) {
+			value = value.substring(0, getMaxDisplaySize() - 3) + "...";
+		}
+
+		return value;
+	}
+
+	/**
+	 * Update the title with the currently registered information.
+	 */
+	private void updateData() {
+		String main = getMainInfoDisplay();
+		String optSecondary = getSecondaryInfoDisplay();
+		Integer status = getStatus();
+
+		// Cached values can be NULL the first time
+		if (!main.equals(cachedMain)
+				|| !optSecondary.equals(cachedOptSecondary)
+				|| status != cachedStatus) {
+			title.setText(mainTemplate //
+					.replace("${MAIN}", main) //
+					.replace("${SECONDARY}", optSecondary) //
+			);
+			secondary.setText(secondaryTemplate//
+					.replace("${MAIN}", main) //
+					.replace("${SECONDARY}", optSecondary) //
+					+ " ");
+
+			Color bg = getOverlayColor(isEnabled(), isSelected(), isHovered());
+			setBackground(bg);
+
+			if (!hasImage) {
+				remove(statusIndicatorUnknown);
+				remove(statusIndicatorOn);
+				remove(statusIndicatorOff);
+
+				Color k = getStatusIndicatorColor(getStatus());
+				JComponent statusIndicator = statuses.get(k);
+				if (!statuses.containsKey(k)) {
+					statusIndicator = generateStatusIndicator(k);
+					statuses.put(k, statusIndicator);
+				}
+
+				if (statusIndicator != null)
+					add(statusIndicator, BorderLayout.WEST);
+			}
+
+			validate();
+		}
+
+		this.cachedMain = main;
+		this.cachedOptSecondary = optSecondary;
+		this.cachedStatus = status;
+	}
+
+	/**
+	 * Generate a status indicator for the given colour.
+	 * 
+	 * @param color
+	 *            the colour to use
+	 * 
+	 * @return a status indicator ready to be used
+	 */
+	private JLabel generateStatusIndicator(Color color) {
+		JLabel indicator = new JLabel("   ") {
+			private static final long serialVersionUID = 1L;
+
+			@Override
+			public void paint(Graphics g) {
+				super.paint(g);
+
+				if (color != null) {
+					Dimension sz = statusIndicatorOn.getSize();
+					int s = Math.min(sz.width, sz.height);
+					int x = Math.max(0, (sz.width - sz.height) / 2);
+					int y = Math.max(0, (sz.height - sz.width) / 2);
+
+					UIUtils.drawEllipse3D(g, color, x, y, s, s, true);
+				}
+			}
+		};
+
+		indicator.setBackground(color);
+		return indicator;
+	}
+
+	private Image getBlank(boolean error) {
+		Dimension key = new Dimension(getCoverWidth(), getCoverHeight());
+		Map<Dimension, BufferedImage> images = error ? Item.error : Item.empty;
+
+		BufferedImage blank = images.get(key);
+		if (blank == null) {
+			blank = new BufferedImage(getCoverWidth(), getCoverHeight(),
+					BufferedImage.TYPE_4BYTE_ABGR);
+
+			Graphics2D g = blank.createGraphics();
+			try {
+				g.setColor(Color.white);
+				g.fillRect(0, 0, getCoverWidth(), getCoverHeight());
+
+				g.setColor(error ? Color.red : Color.black);
+				g.drawLine(0, 0, getCoverWidth(), getCoverHeight());
+				g.drawLine(getCoverWidth(), 0, 0, getCoverHeight());
+			} finally {
+				g.dispose();
+			}
+			images.put(key, blank);
+		}
+
+		return blank;
+	}
+}
-- 
2.27.0